Applicant's prior U.S. Pat. No. 4,458,889 issued on July 10, 1984 discloses a locking power clamp wherein highly pressurized needle bearings in straight track portions of the clamp actuate links connected to a pivoted clamp arm.
Customers of De-Sta-Co Division, Dover Resources Inc., assignee of said patent, have reported that certain conditions such as welding may create an atmosphere having substance which clings to the clamp components. This substance sometimes lands on the bearing tracks and is picked up by the rolling bearings. As the bearings continue to roll back and forth they may pick up more material on their diameters (snowball effect) and eventually stop further roller travel.
Attempts have been made to cover the track area with tape, as disclosed in said patent, or with boots to prevent buildup, which have not always completely or most effectively solved this particular problem.
Shaft wipers are known in the art as well, as slide wipers, generally made of rubber or felt materials; but no such known prior art would be entirely suitable for solving the roller buildup problem in the tracks of the power toggle clamp in question.